In an electronic apparatus, a board on which an IC (including LSI (Large Scale Integration)) is mounted, is housed in a casing.
Recently, ICs have come to be formed as SoCs (System on Chip). According to the SoC, although the versatility is degraded, compared to a case where a series of functions are implemented by using a plurality of general-purpose semiconductor chips, a decrease in the occupant area, an increase in speed, and a decrease in power consumption can be achieved.
In an electronic apparatus, as a transmission medium for data transmission between an IC and another IC mounted on the same board, an IC mounted on a different board, or the like, for example, a metallic line that is a conductive body made of metal or the like is used. Accordingly, in an IC, as an input/output interface used for transmitting and receiving signals to or from an external circuit, an input/output interface that transmits and receives signals through a metallic line is used.
However, in communications (data transmission) through a metallic line, for the wiring of the metallic line, there may be a restriction on the arrangement of an IC on a board or the arrangement of a board in a casing of an electronic apparatus.
Thus, a signal processing device that transmits signals between circuits through wireless communication via free space has been proposed (for example, see JP-A-2003-179821).
According to wireless communication via free space, compared to communication through a metallic line, the degree of freedom of the arrangement of an IC on a board or the arrangement of boards inside a casing of an electronic apparatus can be improved.